Organic Chemistry

Organic Chemistry

Molecular compounds containing carbon atoms

Alkanes/Saturated Hydrocarbons

Carbons atoms containing single covalent bonds

Structural Isomers

When a compound has the same formula but different ways of bonding/forming

Alkyl Group

Hydrocarbons branched off from the main carbon chain

Substituent Group

Any atom or group that replaces a hydrogen in the main chain (can be halogen or alkyl group)

Naming Alkanes

1. Identify the longest carbon chain - This is the parent chain and gives the base name (e.g., methane, ethane, etc.).

2. Number the chain - Start numbering from the end nearest a branch/substituent.

3. Identify and name substituents - Locate any alkyl groups (methyl, ethyl, etc.) attached to the main chain. —> Suffix -ane

4. Assign position numbers - Specify the carbon number for each substituent’s position.

5. Combine substituent names and numbers - List substituents in alphabetical order with position numbers before each, then add the parent chain name.

Cyclic Hydrocarbons

Named the same as any alkane, however, the prefix cyclo- would be used

Alkanes, Alkenes, Alkynes

Alkanes - Hydrocarbons with only single bonds

Alkenes - Hydrocarbons with double bonds

Alkynes - Hydrocarbons with triples bonds

Properties of Alkanes, Alkenes, Alkynes - Intermolecular Force

ONLY London Dispersion Force: Due to its non-polar nature the molecule will have lower M/B points.

• M/B points depend on carbon chain length.

• More Carbons = Higher M/B Point

Highest M/B Points

Alkynes > Alkenes > Alkanes

Solubility of Saturated and Unsaturated Hydrocarbons

Due to their non-polar nature, they are hydrophobic, meaning they are typically insoluble in water since it is polar

Cis and Trans Isomers

Trans Isomers: When matching alkyl groups are on opposite sides

Cis Isomers: When matching alkyl groups are on same sides

Properties of Cis and Trans Isomers

Properties	Cis Isomers	Trans Isomers
Polarity	Polar - Dipoles from the substituent can add up creating a dipole moment	Non-polar - Dipoles from opposite ends tend to cancel each other out
Boiling Point	Higher - Bent shapes allow for additional attractions	Lower - Linear shape limits the # of attractions
Melting Point	Lower - Bent shape can also prevent crystal lattice structure	Higher - Linear shape is more likely to have a crystal lattice structure
Solubility	Soluble in polar solvents	Soluble in non-polar solvents

Properties of Halides

Greater polarity = increase in intermolecular forces thus producing a higher boiling/melting point

Properties of Aromatic Hydrocarbons

Typically non-polar due to the symmetrical structure cancelling the polar bonds out, thus leading to most molecules being insoluble in water.

Properties of Alcohols

Intermolecular Forces:

1. Hydrogen Bonding —> Due to the -OH

2. Lodon Dispersion

Due to the hydrogen bonding, the Melting and Boiling point will be higher compared to alkyl groups

Polarity: Highly polar due to the oxygen’s electronegativity

Solubility: Highly soluble up to 3 carbons then solubility starts to decrease

Liquid up to 12 carbons

Properties of Ethers

Intermolecular Forces

1. London Dispersion Force

2. Dipole-Dipole —> No H-Bonds due to lack of Hydroxyl groups

Melting and Boiling points are lower than alcohols but higher than alkyl groups due to the Dipole-Dipole force.

Polarity: Moderately polar due to electronegativity

Solubility: Soluble with low mass but insoluble with higher mass

Properties of Aldehydes

Intermolecular Forces:

• Dipole Dipole - Due to double bonded oxygen

• LDF

Polarity: Very polar due to dipole-dipole and the double bonded oxygen causing a higher dipole moment

Boiling and melting points are greater than ethers but lower than alcohols (hydrogen bonding)

Solubility: Very soluble for smaller aldehydes but the bigger they get solubility decreases —> Less soluble than alcohols but more soluble than hydrocarbons

Properties of Ketones

Intermolecular Forces

• Dipole-Dipole: Due to the polar carbonyl (C=O) group.

• London Dispersion Forces (LDF): Present in all ketones and increase with molecular size.

Polarity: Moderately Polar due to Carbonyl group creating a dipole, but slightly less polar than aldehydes due to two alkyl groups around the carbonyl.

Boiling and Melting Points: Higher than Ethers (due to dipole-dipole interactions) but lower than Alcohols (no hydrogen bonding).

Solubility: Very soluble for smaller ketones (miscible in water). Solubility decreases with chain length—less soluble than alcohols but more than hydrocarbons.

Properties of Carboxylic Acids

IMF:

• Hydrogen Bonding: hydroxyl group

• Dipole-dipole: double bonded oxygen

• LDF

Polarity: Highly polar due to the H-Bondings and Dipole-dipole

Boiling/Melting Point: Higher melting points than alcohols

Solubility: Similar to alcohols - Molecules with 1-4 carbons are highly soluble, but 5+ has lower solubility

Properties of Esters

IMF:

• Dipole-dipole - Double bonded Oxygen (no hydrogen bondings)

• LDF

Polarity: Moderately polar and is less polar compared to carboxylic acids and alcohols

M/B Point: Esters have lower boiling points than alcohols and carboxylic acids of similar molecular weight.

Properties of Amines

IMF:

• H-Bonding (only primary or secondary)

• Dipole-dipole - created by the lone pair on the nitrogen

• LDF

Polarity: Moderately polar, higher polarity than ketones but lower than alcohol

M/B Point: Higher than alkanes but lower than alcohol

Solubility: Smaller amines are soluble

Properties of Amides

IMF:

• H-Bonding (only primary or secondary)

• Dipole-dipole - created by the lone pair on the nitrogen

• LDF

Polarity: Very polar due to the carbonyl and amine groups

M/B Point: High M/B Point due to h-bonding

Solubility: Smaller amines are soluble

List each organic compound from lowest to greatest polarity

1. Alkanes

2. Alkenes = Alkynes

3. Ethers

4. Esters

5. Aldehydes

6. Ketones

7. Amines

8. Alcohols

9. Amides

10. Carboxylic Acids

List each organic compound from lowest to greatest M/B Point

1. Alkanes

2. Alkenes

3. Alkynes

4. Ethers

5. Esters

6. Aldehydes

7. Ketones

8. Amines

9. Alcohols

10. Amides

11. Carboxylic Acids